“If vegetation exists on Mars, as Prof. Lowell would have us believe, the existence of a flora is ground for suspecting a fauna. On Mars we find ourselves confronted in the canals and oases by precisely the appearance which the planet should show if it is an inhabited world. Dearth of water is the key to the character of the canals. The only available water on Mars is that coming from the semi-annual melting at the one or the other cap of snow. If there are intelligent beings on Mars, they must find some means of conducting the scant supply of water from the poles to the centers of populations.”

Scientific American, July 1907

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